1. Field of the Invention
The present invention relates to a position detector, and more specifically to an absolute position detector which employs a magnetic sensor and which is adapted to detecting an absolute position.
2. Description of the Prior Art
The inventors have previously developed a magnetic rotary sensor that employs a magnetic sensor and that works as an absolute position detector, as disclosed in Japanese Patent Laid-Open No. 108193/1984.
Namely, there is disclosed a magnetic position sensor in which a rotary drum is provided with a plurality of tracks, each track having a plurality of unit magnets, in order to eliminate magnetic interference among the tracks. However, this position sensor requires a magnetic track for each bit of the detecting output signal. To increase the resolving power therefore, the number of magnetic tracks must be increased in proportion thereto, resulting in an increase in the size of the sensor.